HMOX1 and cancer: However, our previous study that followed cancer-free individuals through a linkage to registry database indicated that the short (GT)n polymorphism (<27 (GT)n), which is related to higher levels of HO-1 induction, may nonetheless increase the risk of development of nonmelanoma skin cancer and lung squamous cell carcinoma, but not lung adenocarcinoma or urinary tract cancer [13].